Technical Field
The present invention relates to a radiography apparatus, a radiography method, and a radiography program.
Related Art
In the related art, in a case in which a radiographic image of a subject is captured using radiation that is transmitted through the subject, particularly, in a case in which the thickness of the subject is large, the radiation is scattered in the subject and the scattered radiation (hereinafter, also referred to a “scattered ray”) causes a reduction in the contrast of the captured radiographic image. For this reason, in some cases, a scattered radiation removal grid (hereinafter, simply referred to as a grid) is provided between a subject and a radiation detector in order to reduce the influence of scattered radiation in the capture of a radiographic image. When imaging is performed using the grid, radiation which is scattered by the subject is less likely to reach the radiation detector. Therefore, it is possible to improve the contrast of the radiographic image (for example, see Japanese Patent Application Publication (JP-B) No. H05-82111, Japanese Patent Application Laid-Open (JP-A) No. 10-262961, and JP-A No. 2004-329783).
In a case in which a radiographic image is captured using a grid process, a grid with appropriate characteristics is used according to, for example, imaging conditions. Therefore, in some cases, when the characteristics of the grid used are set, the burden of the setting operation on a user, such as a technician or a doctor, increases.
However, when imaging is performed using the grid as in the related art, a subject image and a fine stripe pattern (moire) corresponding to a grid pitch are included in a radiographic image, which makes it difficult to see a captured radiographic image. Image processing for removing the stripe pattern is also known (for example, see JP-A No. 2013-172881). In some cases, the processing time increases.
There is a technique that performs image processing for a radiographic image which has been captured, without providing a grid between the subject and a radiation detector, to remove the influence of scattered radiation. In addition, the characteristics of the grid that is assumed to be used can be designated and the amount of removal of scattered radiation can be controlled. Hereinafter, a process that performs image processing on the basis of the characteristics of a grid, which is assumed to be used, to remove the influence of scattered radiation to the same extent as that in a case in which a grid is provided is referred to as a virtual grid process.
In a case in which imaging is performed using the virtual grid process, appropriate characteristics of a virtual grid that is assumed to be used are set according to, for example, the imaging conditions, similarly to a case in which imaging is performed using a grid. Therefore, the burden of a setting operation on the user increases.